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I set up this page to help sort my various writings by topic, since the collection was getting a bit too disorganized for my university web site.

Most entries link to documents posted on my University of Guelph web site. A couple of papers appear in under two headings.

(**)
denotes peer-reviewed; i.e. a standard journal process where the article is
read by expert reviewers and may be rejected depending on the referees’
verdict.

(*)
denotes peer-assessed; i.e. a review where changes can be required but the
reviewers do not normally make a recommendation concerning whether to publish
or not once the publisher has solicited the contribution.

CONGRESSIONAL BRIEFING ON CLIMATEGATE: Steve McIntyre and I spoke in the Senate Building in Washington DC on June 17 2010, sponsored by the Competitive Enterprise Institute. My presentation is here in PDF format.

INTER-ACADEMY REVIEW of the IPCC: I was asked by the IAC to submit a set of answers to their queries as part of a review of the policies and procedures of the IPCC. My submission is a bit long, but should make their task much easier.

CRU UPDATE: The UK House of Commons Inquiry into Climategate punted most of the hard questions over to the Review led by Sir Muir Russell. To make sure they receive the pass I sent them a letter today.

GATEKEEPING: I've published in both the economics and climatology fields. Like most academics I have my complaints about both trades. But climatology is simply going off the scale in terms of journal malpractice. The public has acquired a dim view of the credibility of climate science, and based on what I have seen, the public is right. Here is why I think that. (Update: see note at start about BAMS).

SURFACE TEMPERATURES: In 2007 I published a paper with Pat Michaels showing evidence that CRU global surface temperature data used by the IPCC are likely contaminated due to socioeconomic development and variations in data quality. In 2008 Gavin Schmidt published a paper in the International Journal of Climatology claiming our results, as well as those of de Laat and Maurellis who independently found the same things we did, were spurious. My rebuttal, coauthored with Nicolas Nierenberg, was submitted to the IJOC in April 2009. The current version is:

We found out in February that it has been rejected. Interestingly, it turns out that the IJOC had sent Schmidt's paper, which focuses on defending Phil Jones' CRU data against its various critics, to be reviewed by none other than Phil Jones of the CRU. As you can imagine the review was rather enthusiastic and uncritical. The IJOC didn't ask deLaat or me to supply a review, nor did they invite us to contribute a response. And they have rejected the response we did submit, on the basis of some loopy referee reports to which Nico and I were not given a chance to reply (though we did anyway). Nice way they run a journal over at IJOC. The paper is being upgraded and submitted elsewhere. UPDATE: June 2010. The paper's been accepted subject to revisions. Details to come.

I
have written quite a bit on this, including a book, journal articles,
think-tank reports and media op-eds. In general I’m trying to get out of the
area, but as the saying goes, touch the devil and you can’t let go.

Global Warming – CO2 Emission Trends

I
am interested in the question of what future global CO2 emissions
will be and how the IPCC forecasts them. I think the IPCC has exaggerated likely
future emission trends. This conclusion is based on empirical work (coauthored
with Mark Strazicich and Junsoo Lee) which is undergoing the long, slow journal review
process. The Fraser Forum article and the Post op-ed give the gist of the
argument, but the article under review goes into a whole lot of econometric
detail and provides a theoretical growth model to explain why the empirical
results make sense, and why settling the related issue of “convergence” will be
important for constraining future emission forecasts.

Spring 2010: The paper continues to bump along. We spent 18 months going through 3 rounds at one top journal, but there was one (of 3) referees who just hated the paper and would not allow it to be published, despite the fact that we rebutted all his or her objections. Then we went through 3 rounds with another journal, and in the process of dealing with the new referee comments we've expanded the paper quite a bit. (Next they'll tell us it's too long.) We added a 3rd author, Junsoo Lee, who helped us with the Bayesian forecasting section. The last round took 15 months to get referee replies, and the editor ended up adding a new referee who insisted on rejecting the paper based on the claim that our results couldn't be replicated. We got the referee's code and found the error in it, but the editor wouldn't reopen the matter, so it's now under review somewhere else.

We had an exchange with Bjart Holtsmark about the main results of the paper in 2006 in Environment and Energy, at which time we did not know how delayed eventual publication would be. Since we did not want to break the embargo on our paper by presenting the contents in E&E, we only published a brief reply inviting readers to contact us for the more detailed version. Today (April 17 2010) we got our first request. It's been long enough that the reply needed a re-write, and there's not much point keeping it hidden, so here is the updated version:

which carries the story up
to early 2005 when our papers in GRL and E&E had just come out. That was
the end of the technical issues, but the process carried on in the form of the
expert panel of the US National Academy of Sciences, and the Wegman Committee reports. We were asked to meet the NAS panel and make a presentation, whereas the Wegman Committee conducted its work without our input. I have summarized the outcomes in these op-eds:

Nothing that appeared in
print thereafter added anything of real importance to what was in that paper.
Some of the subsequent papers, like Ammann and Wahl’s submission to Climate
Change, just re-hashes trivial arguments that were already dealt with in that
paper.

The key paper in terms of
cracking open the professional debate was our GRL paper:

Two comments were submitted
to GRL by Wahl/Ammann and Ritson, both of which were peer-reviewed and rejected
(in part because they belabour points already resolved in our E&E paper).
Two comments were also submitted by von Storch/Zorita and Huybers, and these
were accepted (along with our replies). The von Storch/Zorita one is rather
pointless, it merely presents a contrived case in which the PC distortion
doesn’t matter. Our reply presented the reasons why their example was
irrelevant to understanding the Mann data set, and along the way we present
some pretty excruciating findings about how little temperature information is
in the Mann data set. Huybers made a legitimate argument about how the RE score
should be benchmarked, which prompted us to revise some calculations.

In 2009, Steve McIntyre and I published a letter in Proceedings of the National Academy of Sciences arguing that a recent paleoclimate reconstruction by Mann et al. does not provide reliable evidence about climate change over the past millennium, because their data are inconsistent and their confidence intervals are wrong.

YAMAL DATA and the other hockey sticks: I published a column in the National Post on Friday October 2, discussing Steve McIntyre's unraveling of the Yamal paleoclimate data and why it is important.

There are other writings
and links available at the M&M page,
such as our NAS submissions.

Global Warming – Temperature Data

In 2008 wrote a working paper about claims in the IPCC 4th Assessment Report that the strong correlation between spatial warming patterns and the spatial pattern of industrialization is a fluke due to atmospheric circulations. The IPCC made this claim without supporting evidence, and used it to sweep aside evidence that their fundamental temperature data are contaminated with a strong warm bias. My paper shows their claim is false. After a long strange trip, and several revisions, my paper has been accepted for publication at a good quality applied statistics journal. I'm not going to say which one just at the moment because of the demonstrated habit of the climategate principals (see pp. 58-60 at the link) not only to blackball journals and editors who publish papers they don't like, but to try and block publication if they get advance warning of the impending appearance of such a paper.

Temperature
data around the world is collected for meteorological purposes. Climate data is
something different, and has to be produced by a model, using temperature data
as an input. The model is intended to “fix” known sources of contamination due
to land use changes, inconsistent quality control etc. Yet the validity of the
models used to produce climate data has been subject to little formal testing,
and what testing has been done points to serious problems. My 2004 work with
Pat Michaels showed that the “corrections” being commonly applied do not correct
the contamination, and leave a strong warming bias in the global land record.

Since
I publish my data and code along with the papers, these results were heavily
scrutinized. A blogger found a small numerical error: I omitted to convert the
latitude measure to radians (from degrees) prior to computing the cosine. This
had only a trivial effect, but many climate scientists dismissed or ignored all
the results largely on the basis of rumours that the results had been
undermined. We published an Erratum right away, putting the before and after
results side-by-side so people could see how small the changes were. The Erratum is posted at:

There
was also a strange comment on our work submitted to Climate Research. It was
not peer-reviewed, instead the Editor just told us to write a response and,
after editing, he published it with the comment. The author found that if he
discarded half the data he got weaker results. Well surprise surprise. Here’s
our response.

After
that paper was published we extended the study to a global sample, and I built
a new socioeconomic data base, adding new covariates and going to a complete
coverage of the available land surface. The new results fully confirm the old
ones: the global land-based surface data set is heavily contaminated by
extraneous ‘signals’ arising from land-surface modifications and variations in
quality control. In a new paper we estimate the overall impact on measured warming over land and discuss the implications for understanding climate data. It’s high time for a much
deeper re-examination of basic climate data sets.

CRU DATA: I have been contacted by several people, including a reporter, asking for supporting information regarding my July 2009 request for the raw data used in the CRU gridded temperature products. This has arisen in part because of Pat Michael's NRO article "The Dog Ate Global Warming." The documentation of my request is here.

A while ago I saw a fascinating essay by Joe D'Aleo on the sudden loss of measurement sites around 1990. I graphed it up and the graph has since been used by a number of other authors, including Marlo Lewis in his book 'A Skeptics Guide to Global Warming'. A detailed explanation of that graph and its origins is here:

In my ‘T3’ chapter (see T3
Tax section below) I discuss the laughable excuse recently provided by the IPCC for
ignoring Pat Michaels’ and my work on the data contamination problem. My criticism of global
temperature data does not end there. In Taken
By Storm Chris Essex and I explained in informal terms why there’s no such
thing as a “global temperature.” We spelled out the theoretical argument in
this paper:

The implications are very
important. The notion of a planet “warming” or “cooling” is ill-posed, at least
in the context of the global warming discussion. Talking about a trend in a
temperature average over a non-equilibrium system as if it is denotes “warming”
(i.e. an increase in a number known to be a temperature) is scientific
hand-waving and short cut-taking that conceals nontrivial physical problems. Every
field (including economics) has to take short-cuts, but eventually when the
discrepancies are piling up all around, someone has to go back and see where
the wrong turn was. I figure people in the climate field will come looking for
this paper in about 10 years.

AMPLIFICATION RATIOS: I was drawn into the dispute between Gavin Schmidt and Klotzbach et al. (see Pielke Sr.) over the latter paper's conclusion that the surface temperature record over land has a warm bias for the purpose of measuring global warming. I was cited in Klotzbach et al. as the source of a claim that the GISS model exhibits amplification over land of about 1.2. I should not have been cited, since all I did was report in an email to John Christy the average trop/surf trend in Gavin Schmidt's own GISS data pertaining to my 2007 surface temperature analysis. The information source, in other words, was Schmidt himself, not me; and in any case I did not provide it as a personal communication for the purpose of a journal article (which I did not know was being written). Phil Klotzbach and his coauthors have issued a correction on this point. In subsequent correspondence with Gavin Schmidt he reported to me that he had corrected an error his original IJOC archive and also that the GISS model classifies land differently than CRU so some of the 440 grid cells are actually over ocean in his model. He supplied me with the GISS landmask. I have recomputed the original results using the corrected data and the GISS landmask. The cosine-weighted amplification ratio over land is about 1.106 and over ocean is 1.602, where 'land' and 'ocean' are according to the GISS landmask applied to the 440 grid cells used in my 2007 paper.

This next article was
invited by the late Kirill Kondratiev. I apply some basic econometrics to
temperature data to show that inference about trends (i.e. deciding whether a
trend is significant or not) requires some careful testing and estimation. This
topic was also waved away by the IPCC (at issue was the work of some others who
examined long term persistence in temperature records). I discuss that in the
T3 chapter. It’s a worthwhile expository paper for people who want to see how
to apply some time series methods to temperature data.

Chris
Essex and I talk at length about the IPCC and its deficiencies in our book Taken
By Storm.

I
also discussed specific criticisms of how the IPCC operates in the following
presentations, one of which became a book chapter and the other appeared in the
Canadian Journal of Agricultural Econonomics.

I
was an expert reviewer for the recent AR4. I found a lot of the report was fine
and indeed well-done. But there are, so to speak, two IPCC reports. One is the
large number of chapters and sections that describe the climate topic in all
its complexity: limitations of models, ambiguity of data, difficulty of explaining
changes, uncertainty over basic ideas, etc. Little of that material makes it
into the widely-read summaries. The other IPCC Report is the AR4 material on
surface temperature data, paleoclimate reconstructions and “attribution”. These
sections are heavily spun and the Summary for Policy Makers then draws
primarily on them. It seemed to me last year, in advance of the release of the
IPCC Report, that there was a need for an Independent Summary for Policy
Makers. Fortunately I was able to find a high quality group of contributors to
work on it, and the Fraser Institute agreed to publish it. Our ISPM was
reviewed by 65 experts, and unlike the IPCC we tabulated their responses. I
remain convinced that if both the IPCC SPM and our ISPM were assessed by all the members
of, say, the American Meteorological Society, ours would be given higher marks.
I still use it as a reference guide to the IPCC Report.

It's an approachable but technical treatment of 8 important issues the IPCC either ignores or gets wrong.

At the time of the release
of the IPCC Summary, Newsweek contacted me for an interview. By the end of it,
the editor I spoke to decided they could not really fit what I had to say into
a story, and they invited me to write a column instead.

In Fall 2007 I gave a talk at a conference sponsored by the American Institute for Economic Research, where I was a respondent to a presentation by David Henderson entitled "Governments and Climate Change Issues: the Flawed Consensus." In my remarks I discuss a series of examples drawn from my observations acting as an IPCC reviewer which, in my view, establish a disturbing pattern of bias on the part of the IPCC. I also explain how I think it should be fixed.

Overall
I am very skeptical about the idea that global warming is a scientifically
well-defined concept, that it is known to be driven by CO2emissions and will cause a dangerous crisis
for the world. Consequently I think policies to reduce CO2emissions are likely to be a waste even if
well-designed, and much moreso when they are ill-conceived. But I know a lot of
people are worried about it, and I can’t blame them since the media tsunami on
this topic in recent years all but forbids dissent, unless you are equipped
with a lot of detailed counter-information or you just have a very good BS
detector.

Recently
I came up with a policy proposal that reconciles my skepticism with the policy
activism of the alarmists: calibrate a carbon tax to the average temperature of
the region of the atmosphere predicted by climatologists to be most sensitive
to CO2. I call it the ‘T3’ tax, and I think the proposal should make
everyone happy, except the most extreme alarmists and the Trojan horse-types
who see the global warming issue as a vehicle for imposing a set of anti-growth
policies that they would want even if global warming fizzles as a pretext. The
Post op-ed explains the T3 concept briefly. It got a lot of attention on the
internet (partly through a headline link on Arts and Letters Daily). The Vancouver Volumes chapter develops the
idea in full technical detail. I also did a recent interview about the T3 Tax on the Australian radio show Counterpoint (ABC). The 4-page E&E edition is a forthcoming commentary in Environment and Energy. It provides a more detailed summary than the Post op-ed.

The Ottawa Economics
Association invited me to address the question of Canada’s options on global
warming policy, on the eve of the new Conservative government’s announcement.
In this paper I explain why pricing instruments are preferred to quantity
targets, and what the literature says about the approximate marginal damages
due to CO2 emissions.

During the debate over
whether Canada should ratify Kyoto, Randy Wigle and I published
(through the CD Howe Institute) a critical review of the federal government’s
work on implementation costs. A little later I was asked to discuss the
government’s plans as they were reflected (or not) in the 2003 budget, for a
conference at Queen’s University.

I recently gave a talk at Wilfrid Laurier University's Viessmann European Research Centre, comparing US and European approaches to climate change. My point was that while they have outlined different objectives, the constraints are so tight that the outcomes are pretty much the same.

This little paper sets out
an argument that if we are unable to tell, ex post, whether a given weather
event was due to global warming or not, we are unlikely ever to be able to
compute the marginal damages due to carbon dioxide emissions. As such, we are
better off planning to compensate victims ex post rather than trying to
mitigate damages ex ante. If I was smarter and less distracted I would develop
it into a more formal revision to the Integrated Assessment Model approach,
which assumes away all the uncertainty over attribution.

I wrote this paper for the
Competitive Enterprise Institute (they paid me a thousand bucks) explaining why
cap and trade and similar methods for controlling CO2 emissions are
bad ideas. I will have a new report for CEI this year going into more detail in
light of the proposals before the US Congress.

This paper came out of my
PhD thesis work, using a computable general equilibrium model to show that
revenue-neutral carbon taxes can achieve some emission reductions at no net
macroeconomic cost. It wouldn’t get us to the Kyoto target, but I do believe
that a low carbon tax of up to about $20 per tonne, if fully recycled into
payroll and income tax cuts, would not harm the economy. Of course it wouldn’t
reduce emissions much either.

This
is da book. The revised edition came out in Canada in Fall 2007 and in the US in Spring 2008. Publication in the rest of the world will occur in late 2008. It’s the best book
out there on the subject, in my view, combining some irreverent humour with a
serious presentation of the science, economics and social dynamics of this
issue. Ideas sketched out in TBS provide a guide to what is now playing out in
the scientific literature, and will be for many years to come (I know I know -- arrogant of me to say. But just watch.)

In August 2008 I was asked by the Manning Centre in Calgary to speak at a course for journalists on public policy issues. The specific topic given to me was "Questions every journalists should ask about global warming." My presentation was pretty well received (whether it changes the way global warming gets reported on in Canada is another matter).

In December 2008 I made a
Submission to the US EPA in response to its Advance Notice of Proposed Rulemaking for greenhouse gases.

It includes my letters to Inhofe and Dingell as well as some supplementary material.

In October 2008 I was sent a list of questions from Senator Inhofe of the US Environment and Public Works Committee, concerning the validity of climate models in view of the plans to regulate greenhouse gases. My response is here:

Following my
June 2008 testimony to the US House Committee on Energy and Commerce I was issued a set of follow-up questions by Chairman Dingell. My response is here.

On June 26 I testified before the US House of Representatives Subcommittee on Energy and Air Quality. My spoken comments were only about 4 minutes (not as long as what's written here) but I made an extended submission.

In September 2007 I was contacted by a politician outside of Canada who was preparing for cabinet-level decisions on global warming policy. I was asked to identify half a dozen of the main assumptions about global warming that, if wrong, would invalidate the usual conclusions. Of course the topic is so big I could easily have written a book in response. A tidied-up version of my actual reply is here. I do not know what effect, if any, it had on the individual's views.

On
occasion I have been encouraged to put in a submission to ongoing inquiries.
These two went to the Australian Parliament and the UK House of Lords. In each
case the outcomes were actually pretty good, so maybe it was worth the effort.

Lately
I have been working on conventional urban air quality topics, including
explaining the link between economic growth and air pollution, and
re-evaluating the evidence for a health impact.

Air Pollution – Economics

I am interested in how
economic growth relates to urban air quality. This paper presents a VAR-based
model for analyzing the question and provides some plausible answers to what
caused the postwar decoupling of US growth and pollution.

My one foray into the
political science of environmental policy argues that Canadians have not
historically based their votes on environmental outcomes. Despite all the
current hoopla about the environment being at the top of the polls, I still
expect that it does not affect party preferences that are formed on other bases
than environmental platforms.

The Fraser Institute is
putting out a book on Canadian environmental policy. I wrote the chapter on air
pollution, and I think it does a good job explaining the current situation and
proposing how future developments should be focused. I was writing it while the
federal Conservatives were floundering around with their Green Plan, whose eventual form I think was pretty inferior.

I have been doing some work
on the connection between air pollution and health (or lack thereof). I have published a
paper coauthored with Lise Tole and Gary Koop. I also
wrote about the topic in some of the above papers, such as the Fraser Institute
study on Ontario’s coal plants. Also included here are a
talk I did to AMPCO in 2004 and a couple of op-eds from the National Post.

ENVIRONMENTAL ECONOMICS

Theory of Policy Design

Economics has a great deal to say about how to design policies that minimize the costs of achieving public objectives, as well as what those objectives ought to be. My contributions include a look at how a nonlinear tax system can achieve the right outcome when the regulator lacks information on private costs, what the optimal entry/exit condition is for a polluting industry, and how to improve the efficiency of ratio or intensity standards. Contact me if you want a reprint of any of these.

SCIENCE AND PUBLIC POLICY

Being an economist, but
having also worked on physical science issues, my thoughts have occasionally
turned to the institutions used to apply scientific information to policy
formation.

Science and Public Policy - Use of science in
public policy formation

As
a result of the hockey stick episode I got interested in the issue of how and whether scientific information should be audited by users, in particular by a government considering a multi-billion dollar public
policy decision based on findings in scientific research papers. Bruce McCullough (Drexel University) and I released a study through the Fraser Institute that looks at problems of data secrecy in academia and its effects on public policy formation.

The following two papers were also listed in other sections above. They set down my initial thinking on the subject of fixing the process by which scientific information is assembled for use in policy formation.
Also see Taken By Storm Chapter 10.

In addition to everything here, I have published some
book reviews, other op-eds etc. If you are sure I wrote it and it’s not here,
you can email me.

GLOBAL FINANCIAL CRISIS

I have written a series of articles in the Financial Post on the current economic crisis. Judging by the reaction so far, people seem to appreciate having some of these rather complex issues explained in plain language.